HTML-Parser/lib/Data.php
J. King 164e5ff1e8 Add standard charset detection tests
- Various new tests needed for full coverage, noted in comment
- Byte Order Mark detection methopd added
- Japanese encodings nt yet supported, so tests marked incomplete
- Tests requiring scripting suppressed
2019-12-22 22:51:18 -05:00

305 lines
11 KiB
PHP

<?php
declare(strict_types=1);
namespace dW\HTML5;
use MensBeam\Intl\Encoding;
use MensBeam\Intl\Encoding\Encoding as EncodingEncoding;
class Data {
use ParseErrorEmitter;
// Used to get the file path for error reporting.
public $filePath;
public $encodingCertain = false;
// Internal storage for the Intl data object.
protected $data;
// Used for error reporting to display line number.
protected $_line = 1;
// Used for error reporting to display column number.
protected $_column = 1;
// array of normalized CR+LF pairs, denoted by the character offset of the LF
protected $normalized = [];
// Holds the character position and column number of each newline
protected $newlines = [];
// Holds the character position of each supplementary plane character, which count as two columns when reporting errors
protected $astrals = [];
// The character position of the forward-most input stream error emitted
protected $lastError = 0;
// Whether the EOF imaginary character has been consumed
protected $eof = false;
const ALPHA = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
const DIGIT = '0123456789';
const HEX = '0123456789ABCDEFabcdef';
const WHITESPACE = "\t\n\x0c\x0d ";
public function __construct(string $data, string $filePath = 'STDIN', ParseError $errorHandler = null, string $encodingOrContentType = '') {
$this->errorHandler = $errorHandler ?? new ParseError;
if ($filePath !== 'STDIN') {
$this->filePath = realpath($filePath);
$data = file_get_contents($this->filePath);
} else {
$this->filePath = $filePath;
}
if ($encoding = Charset::fromBOM($data)) {
// encoding determined from Unicode byte order mark
$this->encodingCertain = true;
} elseif ($encoding = Charset::fromCharset($encodingOrContentType)) {
$this->encodingCertain = true;
} elseif ($encoding = Charset::fromTransport($encodingOrContentType)) {
$this->encodingCertain = true;
} elseif ($encoding = Charset::fromPrescan($data)) {
// Encoding is tentative
} else {
// Encoding is tentative; fall back to the configured default encoding
$encoding = Parser::$fallbackEncoding;
}
$this->data = Encoding::createDecoder($encoding, $data, false, true);
}
public function consume(int $length = 1, $advancePointer = true): string {
assert($length > 0, new Exception(Exception::DATA_INVALID_DATA_CONSUMPTION_LENGTH, $length));
for ($i = 0, $string = ''; $i < $length; $i++) {
$char = $this->data->nextChar();
# Before the tokenization stage, the input stream must be
# preprocessed by normalizing newlines.
# Thus, newlines in HTML DOMs are represented by U+000A LF characters,
# and there are never any U+000D CR characters in the input to the tokenization stage.
if ($char === "\r") {
// if this is a CR+LF pair, skip the CR and note the normalization
if ($this->data->peekChar() === "\n") {
$char = $this->data->nextChar();
$this->normalized[$this->data->posChar()] = true;
}
// otherwise just silently change the character to LF;
// the bare CR will be trivial to process when seeking backwards
else {
$char = "\n";
}
}
// append the character to the output string
$string .= $char;
// unless we're peeking, track line and column position, and whether we've hit EOF
if ($advancePointer) {
if (!$this->checkChar($char)) {
break;
}
}
}
return $string;
}
protected function checkChar(string $char): bool {
// track line and column number, and EOF
if ($char === "\n") {
$this->newlines[$this->data->posChar()] = $this->_column;
$this->_column = 1;
$this->_line++;
} elseif ($char === '') {
$this->eof = true;
return false;
} else {
$len = strlen($char);
$here = $this->data->posChar();
if ($this->lastError < $here) {
// look for erroneous characters
if ($len === 1) {
$ord = ord($char);
if (($ord < 0x20 && !in_array($ord, [0x0, 0x9, 0xA, 0xC])) || $ord === 0x7F) {
$this->error(ParseError::CONTROL_CHARACTER_IN_INPUT_STREAM);
$this->lastError = $here;
}
} elseif ($len === 2) {
if (ord($char[0]) == 0xC2) {
$ord = ord($char[1]);
if ($ord >= 0x80 && $ord <= 0x9F) {
$this->error(ParseError::CONTROL_CHARACTER_IN_INPUT_STREAM);
$this->lastError = $here;
}
}
} elseif ($len === 3) {
$head = ord($char[0]);
if ($head === 0xED) {
$tail = (ord($char[1]) << 8) + ord($char[2]);
if ($tail >= 0xA080 && $tail <= 0xBFBF) {
$this->error(ParseError::SURROGATE_IN_INPUT_STREAM);
$this->lastError = $here;
}
} elseif ($head === 0xEF) {
$tail = (ord($char[1]) << 8) + ord($char[2]);
if (($tail >= 0xB790 && $tail <= 0xB7AF) || $tail >= 0xBFBE) {
$this->error(ParseError::NONCHARACTER_IN_INPUT_STREAM);
$this->lastError = $here;
} elseif ($tail === 0xBFBD && $this->data->posErr === $here) {
$this->error(ParseError::NONCHARACTER_IN_INPUT_STREAM, $this->data->posByte);
$this->lastError = $here;
}
}
} elseif ($len === 4) {
$tail = (ord($char[2]) << 8) + ord($char[3]);
if ($tail >= 0xBFBE) {
$this->error(ParseError::NONCHARACTER_IN_INPUT_STREAM);
$this->lastError = $here;
}
}
}
$this->_column++;
if ($len === 4) {
// If the character is on a supplementary Unicode plane,
// it counts as two columns for the purposes of error reporting
$this->astrals[$here] = true;
$this->_column++;
}
}
return true;
}
public function unconsume(int $length = 1, bool $retreatPointer = true): void {
assert($length > 0, new Exception(Exception::DATA_INVALID_DATA_CONSUMPTION_LENGTH, $length));
if ($this->eof) {
$length--;
$this->eof = false;
}
while ($length-- > 0) {
$here = $this->data->posChar();
// if the previous character was a normalized CR+LF pair, we need to go back two
if (isset($this->normalized[$here])) {
$this->data->seek(-1);
}
// recalculate line and column positions, if requested
if ($retreatPointer) {
$col = $this->newlines[$here] ?? 0;
if ($col) {
$this->_column = $col;
$this->_line--;
} else {
$this->_column--;
if ($this->astrals[$here] ?? false) {
$this->_column--;
}
}
}
$this->data->seek(-1);
}
}
public function consumeWhile(string $match, int $limit = 0): string {
return $this->span($match, true, true, $limit);
}
public function consumeUntil(string $match, int $limit = 0): string {
return $this->span($match, false, true, $limit);
}
public function peek(int $length = 1): string {
assert($length > 0, new Exception(Exception::DATA_INVALID_DATA_CONSUMPTION_LENGTH, $length));
$string = $this->data->peekChar($length);
return $string;
}
public function peekWhile(string $match, int $limit = 0): string {
return $this->span($match, true, false, $limit);
}
public function peekUntil(string $match, int $limit = 0): string {
return $this->span($match, false, false, $limit);
}
protected function span(string $match, bool $while = true, bool $advancePointer = true, int $limit = -1): string {
// Break the matching characters into an array of characters. Unicode friendly.
$match = preg_split('/(?<!^)(?!$)/Su', $match);
$start = $this->data->posChar();
$count = 0;
$string = '';
while (true) {
$char = $this->consume(1, false);
if ($char === '') {
break;
}
$inArray = in_array($char, $match);
// strspn
if ($while && !$inArray) {
$this->unconsume(1, false);
break;
}
// strcspn
elseif (!$while && $inArray) {
$this->unconsume(1, false);
break;
}
if ($advancePointer) {
$this->checkChar($char);
}
$count++;
$string .= $char;
if ($count === $limit) {
break;
}
}
if (!$advancePointer && $count) {
$this->data->seek(-($this->data->posChar - $start));
}
return $string;
}
/** Returns an indexed array with the line and column positions of the requested offset from the current position */
public function whereIs(int $relativePos): array {
if ($relativePos === 0) {
return [$this->_line, $this->_column];
} elseif ($relativePos < 0) {
$pos = $this->data->posChar();
$line = $this->_line;
$col = $this->_column;
do {
// If the current position is the start of a line,
// get the column position of the end of the previous line
if (isset($this->newlines[$pos])) {
$line--;
$col = $this->newlines[$pos];
// If the newline was a normalized CR+LF pair,
// go back one extra character
if (isset($this->normalized[$pos])) {
$pos--;
}
} else {
$col--;
// supplementary plane characters count as two
if ($this->astrals[$pos] ?? false) {
$this->_column--;
}
}
$pos--;
} while (++$relativePos < 0);
return [$line, $col];
}
}
public function __get($property) {
switch ($property) {
case 'column': return $this->_column;
break;
case 'line': return $this->_line;
break;
case 'pointer': return $this->data->posChar();
break;
default: return null;
}
}
}